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A CT attempts to push a specific ratio of primary current through the secondary. If the secondary is open circuited, the resistance across the secondary will be very large. Following Ohm's law, V = I*R, so the secondary voltage will become very large, and will arc across the open, or damage the CT, or both.
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How do you connect a diode across a ac coil?
You mean ac coil, the secondary coil, of a transformer? Then for the purpose of rectification, that is , for changing ac into dc, a diode is connected in series with the secondary coil of the transformer.
Can you saturate a CT with the secondarys shorted?
A CT becomes saturated when the induced secondary voltage is beyond the capabilities of the CT. Yes it is possible, if enough current is forced through the secondary to raise the voltage beyond the CT capability curve. Remember the CT has inherent resistance due to the secondary winding. That said, to saturate strictly based on the CT resistance is unlikely. But it is still theoretically possible.
Why should current transformers be shunted before opening the secondary winding?
A current transformer's secondary must never be open-circuited. If the instrument fed by a CT needs to be removed, then the secondary terminals must be short-circuited first. This is because a large, and potentially-dangerous, secondary voltage will appear across an open-circuited CT. Normally, a set of links is provided at those terminals for this purpose.
What is the current in the secondary coil fi the current in the primary coil is 5.0A 10 loops on primary coil and 20 on secondary coil?
If I am not wrong then you have asked about a transformer. And its a current transformer. By theory of voltage transformer we know that Vs/Vp = Ns/Np So for answering your question we need the value of number of turns in primary and secondary coil. But you can use this equation to find your answer if you have other values. By using ohmic law you can convert voltage to current.
Why should the secondary of a voltage transformer not be short circuited?
A voltage transformer takes a primary voltage and steps it down to a smaller secondary voltage. This type of transformer will attempt to keep the secondary voltage at a specific ratio of the primary voltage. If you short it, massive current flow in the secondary is required to do this. For a similar reason a CT should never be open circuited - because it attempts to push a specific ratio of primary current through the secondary. If you open circuit the secondary, it takes a massive voltage on the secondary to accomplish this.
Why the CT secondary short circuited?
Current transformers produce a ratio of primary current in the secondary. If the secondary of a CT is open circuited, and primary current is flowing, the CT will try to push that same ratio of current through the secondary open circuit. This causes secondary voltage to climb until it the secondary open circuit flashes over. This can often damage the CT.
Why the current coil of ct having less no of turn than pressure coil?
A CT doesn't have a 'pressure coil'! Reword your question.
Why must a fuse or Switch never be fitted to the secondary of a CT circuit?
Secondary of a CT should never be opened to avoid damage to CT. Fuse or switch may lead to opening of CT secondary accidentally.
Difference of step up and step down in terms of no of loops in the secondary coil?
If the primary coil has ten loops and the secondary coil has five loops then the secondary coil works as a 50% step down
Why ct secondary doesnt have fuse?
high voltage can be induced in the ct secondary which may sufficient to cause breakdown of insulation.
What is meant by a primary coil and a secondary coil?
In a transformer, the primary coil is the coil that has voltage applied to it. The secondary coil is the coil that we take voltage from. Transformers are used to step up voltage, step down voltage, or simply to isolate circuits.
How do you connect a diode across a ac coil?
You mean ac coil, the secondary coil, of a transformer? Then for the purpose of rectification, that is , for changing ac into dc, a diode is connected in series with the secondary coil of the transformer.
Can you saturate a CT with the secondarys shorted?
A CT becomes saturated when the induced secondary voltage is beyond the capabilities of the CT. Yes it is possible, if enough current is forced through the secondary to raise the voltage beyond the CT capability curve. Remember the CT has inherent resistance due to the secondary winding. That said, to saturate strictly based on the CT resistance is unlikely. But it is still theoretically possible.
Why should current transformers be shunted before opening the secondary winding?
A current transformer's secondary must never be open-circuited. If the instrument fed by a CT needs to be removed, then the secondary terminals must be short-circuited first. This is because a large, and potentially-dangerous, secondary voltage will appear across an open-circuited CT. Normally, a set of links is provided at those terminals for this purpose.
How does a power mat for an Android device work?
The primary coil is in the power mat while the secondary coil is in the Android device. Power goes from the primary coil to the secondary coil, which allows the phone to charge.
What can cause a coil to short out?
If the coil is overheated it can easily short.
What are the two coils in a transformer?
primary and secondary coilsAnswerPrimary and secondary windings.
